The purpose of Core Project B (Animal Core) is to provide animal models of stroke to projects 2 and 3 of the Stroke Center Program. Animal models provide an opportunity to study the pathophysiological processes operative in stroke in a controlled situation and are an essential link between advances in basic science and clinical medicine. Three rodent models are employed that reproduce different pathophysiological processes thought to be important in determining the outcome of human stroke. These models involve: 1) a global, forebrain ischemia resulting in a delayed and a selective damage of certain vulnerable neuronal populations (e.g. hippocampal CA1 pyramids); 2) a focal forebrain ischemia produced by occlusion of the middle cerebral artery; 3) kainate-induced lesions that destroy neuronal bodies while sparing axons of passage.